Re: Firing Sequential Ignitors with Just One Switch?

Ike wrote: 
Hello...

I'm working with the electrically-fired nichrome rocket ignitors for a
rocketry project.

Is there a way to wire a number of ignitors to a single switch so that
each time you close the switch it activates the next ignitor in the
chain, burning it up, and somehow making the next ignitor ready for
electrical activation?  This would allow, for example, 10 rockets to be
fired in succession by pressing the button 10 times.

I DON'T want to push the button once and fire all 10 electric matches!

If there isn't a way to do this, I will continue with my plan to use a
PIC microprocessor, but that means relays and/or transistors and more
cost if I wanted to control more than 5 or 10 ignitors.

Thank you in advance!

--
--Ike
--


I don't know what your budget is, but a basic PLC - like the pico from A-B - can do that along with inputs from safety observers with kill switches. It has the dry relay contacts to provide the power handling, too. And a nifty little LCD display you can program to show the countdown.....

I'd guess less than $100 for the PLC and a handful of pushbuttons. I think a pico has 12 dry relay contacts. You'd have to chain them together to get more....

For a low-tech alternative, see the nail-and-wire pegboards the fireworks guys use. Basically, a bunch of 12 penny nails with wires; you hit each one in turn to fire the next sequence of fireworks.
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